The primary functions of the Human Subjects Core are as follows. (1) Recruitment of female and male human subjects representing the population of the local community for participation In the longitudinal study of age-related hearing loss and experiments proposed in each project. (2) Collection, storage, and analysis of demographic, audiologic, and biologic/medical data and tissue (blood and DNA) from human subjects enrolling in and continuing in the longitudinal study. These data define the basic demographic, audiologic, and medical profiles of each subject and are organized into a searchable database, which provides key information needed by investigators in each project to select subjects according to the needs of their experiments. (3) Coordination of subject schedules for the audiologic and medical test battery, annual evaluations, longitudinal measures, and visits to the Otolaryngology clinic and to the Clinical Translational Research Center (CTRC) for blood draws. Because of the strong links among projects, there is substantial overlap of needs for subject participation. Thus, a major goal ofthe Human Subjects Core is to make efficient use of subjects' testing time and coordinate storage of their data to optimize data access and analyses across projects.